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531.
This paper is based on the perception that the inertia of climate and socio-economic systems are key parameters in the climate
change issue. In a first part, it develops and implements a new approach based on a simple integrated model with a particular
focus on an innovative transient impact and adaptation modeling. In a second part, a climate–economy feedback is defined and characterized. The following results were found. 1) It has a long characteristic time, which lies between
50 and 100 years depending on the hypotheses; this time scale is long when compared to the system's other time scales, and
the feedback cannot act as a natural damping process of climate change. 2) Mitigation has to be anticipated since the feedback
of an emission reduction on the economy can be significant only after a 20-year delay and is really efficient only after at
least 50 years. 3) Even discounted, production changes due to an action on emissions are significant over more than one century.
4) The methodology of the Intergovernmental Panel on Climate Change (IPCC), which neglects the feedback from impacts to emissions,
is acceptable up to 2100, whatever is the level of impacts. This analysis allows also to define a climatic cost of growth as the additional climate change damages due to the additional emissions linked to economic growth.
相似文献
Stéphane HallegatteEmail: |
532.
Large, multinational resource development projects can affectmany aspects, including social, economic and ecological realities, in the regions where they operate. Social and environmental issues that are usually ignored in such projectsare increasingly affecting the financial future of multinationalcorporations in negative ways. In this article, we advance the argument that corporations can successfully manage these issuesand that if they choose to view these management efforts as an investment rather than an expense, they may well acquire a competitive advantage over companies that do not. We describe asa case study the Camisea natural gas and condensates developmentproject in Peru, operated by Shell Prospecting and Development Peru (SPDP). Camisea is one of the first projects anywhere inthe world to conduct a detailed analysis of key industry-relatedsocial issues and the processes, required investment and financial impact of managing them. The Camisea example supportsthe argument that addressing social and environmental concerns makes financial sense. In present value terms, the benefit ofmanaging these concerns was expected to surpass the cost investment by approximately US$50 million. 相似文献
533.
This study examined the relationship between environmental concern and ratings of acceptability of environmental impacts among visitors at two national park settings. Based on the concept of a social ecological paradigm shift, it was hypothesized that individuals with greater levels of environmental concern are less accepting of environmental impacts in national parks than individuals with lesser degrees of concern. Sample data came from Cape Lookout National Seashore (N=392) and Moores Creek National Battlefield (N=236), two national park units in the south-eastern U.S.A. Environmental concern was measured by the New Ecological Paradigm scale. Acceptability was measured by visitor responses to 25 items covering different types of environmental park impacts. Analysis of variance and Tukey's means comparison procedure were used to test for differences between groups defined by levels of environmental concern on impact acceptability. Significant relationships were found between environmental concern and 15 of the 25 specific impacts in the Cape Lookout sample and 13 significant relationships were found in the Moores Creek sample. However, the relationships between environmental concern and acceptability varied somewhat across the two samples. These findings suggested that individuals with greater environmental concern were less accepting (or tolerant) of certain types of park impacts, while individuals with lesser degrees of environmental concern were more accepting of certain park impacts. Differences across the study settings were attributed to the different orientations of park visitors between the two national park units and recency effects. While the data reported are preliminary, they should be informative for park management purposes, particularly in the determination of standards for park impacts. 相似文献
534.
Environmental concerns such as loss of biological diversity and stratospheric ozone depletion have heightened awareness of the need to assess cumulative impacts in environmental documents. More than 20 years of experience with the National Environmental Policy Act (NEPA) have provided analysts in the United States with opportunities for developing successful techniques to assess site-specific impacts of proposed actions. Methods for analyzing a proposed action's incremental contribution to cumulative impacts are generally less advanced than those for project-specific impacts.The President's Council on Environmental Quality (CEQ) defines cumulative impact to include the impacts of past, present and reasonably foreseeable future actions regardless of who undertakes the action. Court decisions have helped clarify the distinction between reasonably foreseeable future actions and other possible future actions. This paper seeks to clarify how past and present impacts should be included in cumulative impact analyses.The definition of cumulative impacts implies that cumulative impact analyses should include the effects of all past and present actions on a particular resource. Including past and present impacts in cumulative impact assessments increases the likelihood of identifying significant impacts. NEPA requires agencies to give more consideration to alternatives and mitigation and to provide more opportunities for public involvement for actions that would have significant impacts than for actions that would not cause or contribute to significant impacts. For an action that would contribute to significant cumulative impacts, the additional cost and effort involved in increased consideration of alternatives and mitigation and in additional public involvement may be avoided if the action can be modified so that its contributions to significant cumulative impacts are eliminated.Managed by Lockheed Martin Energy Research Corporation under contract DE-AC05-84OR21400 with the US Department of Energy. 相似文献
535.
古村落旅游地利益主体关系及影响研究--世界文化遗产地西递、宏村实证分析 总被引:12,自引:0,他引:12
运用利益主体理论,通过对西递、宏村两地旅游业密切相关的各利益主体代表的访谈及问卷调查发现,政府、居民、旅游企业、游客为目前古村落旅游地最主要的利益主体,他们在古村落的旅游发展中,所处的地位、执行的职能、发挥的作用各不相同,但彼此又密切相关,具有一些共同目标或职责。在此基础上,指出西递、宏村两地旅游发展面临的主要矛盾和问题,提出鼓励公众参与、提高从业人员素质和教育程度、加强对旅游者的教育、加强利益主体之间的协调与合作等相关对策。 相似文献
536.
Kent S. Murray Daniel T. Rogers Martin M. Kaufman 《Journal of the American Water Resources Association》2006,42(3):777-792
ABSTRACT: The occurrence of dissolved heavy metal concentrations in shallow ground water were measured at 126 sites within an urban watershed in southeastern Michigan. A total of 1,140 samples were collected from the first saturated zone, and the mean concentrations of 11 heavy metals (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc) were obtained and compared to their corresponding mean concentrations within surface soil. The results suggest that former and current land use processes have resulted in significant adverse impacts on the study region. Levels of Cr 20 to 30 times the maximum contaminant level (MCL) have been detected in the ground water beneath industrial sites. In addition, Cd and Pb have been found at levels exceeding their MCLs where surface soils are clay‐rich, and in sandy soils at more than 10 times their MCLs. The high levels of Cr in ground water strongly suggest that the chromium is in a hexavalent form, and this likelihood is supported by current studies. Given the hydraulic connection between the watershed's surface waters and the Great Lakes, these findings raise significant ecological and public health concerns. 相似文献
537.
Allison M. Thomson Robert A. Brown Norman J. Rosenberg R. Cesar Izaurralde David M. Legler Raghavan Srinivasan 《Journal of the American Water Resources Association》2003,39(1):137-148
ABSTRACT: The El Nino/Southern Oscillation (ENSO) phenomena alter global weather patterns with consequences for fresh water supply. ENSO events impact regions and their natural resource sectors around the globe. For example, in 1997 and 1998, a strong El Nino brought warm ocean temperatures, flooding, and record snowfall to the west coast of the United States. Research on ENSO events has improved long range climate predictions, affording the potential to reduce the damage and economic cost of these weather patterns. Here, using the Hydrologic Unit Model for the United States (HUMUS), we simulate the impacts of four types of ENSO states (Neutral, El Niño, La Niña, and strong El Niño) on water resources in the conterminous United States. The simulations show that La Niña conditions increase water yield across much of the country. We find that water yield increases during El Niño years across the south while declining in much of the rest of the country. However, under strong El Niño conditions, regional water yields are much higher than Neutral, especially along the West Coast. Strong El Niño is not simply an amplification of El Niño; it leads to strikingly different patterns of water resource response. 相似文献
538.
ABSTRACT: The seemingly magnetic attraction of water resources for recreation has direct implications for proximate land resources which are needed to provide access and support facilities. This paper reviews and synthesizes the literature dealing with the impacts of recreation use on riparian soils and vegetation. Part one of the paper sets forth the major negative impacts of recreation use on soils and vegetation. A seven-step soil impact cycle is identified, beginning with the scuffing away of leaf litter and other organic material and working through the soil erosion and sedimentation process. Four major kinds of impacts of recreation use on vegetation are then outlined, and the‘Vicious circle” relationship between impacts on soil and vegetation is demonstrated through a Soil/Vegetation Impact Diagram. Part two identifies several spatial and temporal patterns of environmental impact caused by recreation use. The node and linkage pattern of recreation use, campground and trail expansion, ground cover response and succession, rates of soil compaction, and resource response to various intensities of recreation use are important aspects. The final part of the paper deals with measuring environmental impacts caused by recreation use. Management implications of the research findings are considered throughout the paper. 相似文献
539.
Cumulative impacts on water quality functions of wetlands 总被引:3,自引:0,他引:3
The total effect of cumulative impacts on the water quality functions of wetlands cannot be predicted from the sum of the effects each individual impact would have by itself. The wetland is not a simple filter; it embodies chemical, physical, and biotic processes that can detain, transform, release, or produce a wide variety of substances. Because wetland water quality functions result from the operation of many individual, distinct, and quite dissimilar mechanisms, it is necessary to consider the nature of each individual process.Sound knowledge of the various wetland processes is needed to make guided judgements about the probable effects of a given suite of impacts. Consideration of these processes suggests that many common wetland alterations probably do entail cumulative impact. In addition to traditional assessment methods, the wetland manager may need to obtain appropriate field measurements of water quality-related parameters at specific sites; such data can aid in predicting the effects of cumulative impact or assessing the results of past wetland management. 相似文献
540.
Eugene Z. Stakhiv 《Environmental management》1988,12(5):725-748
Cumulative impact analysis is examined from a conceptual decision-making perspective, focusing on its implicit and explicit purposes as suggested within the policy and procedures for environmental impact analysis of the National Environmental Policy Act of 1969 (NEPA) and its implementing regulations. In this article it is also linked to different evaluation and decision-making conventions, contrasting a regulatory context with a comprehensive planning framework. The specific problems that make the application of cumulative impact analysis a virtually intractable evaluation requirement are discussed in connection with the federal regulation of wetlands uses. The relatively familiar US Army Corps of Engineers' (the Corps) permit program, in conjunction with the Environmental Protection Agency's (EPA) responsibilities in managing its share of the Section 404 regulatory program requirements, is used throughout as the realistic context for highlighting certain pragmatic evaluation aspects of cumulative impact assessment.To understand the purposes of cumulative impact analysis (CIA), a key distinction must be made between the implied comprehensive and multiobjective evaluation purposes of CIA, promoted through the principles and policies contained in NEPA, and the more commonly conducted and limited assessment of cumulative effects (ACE), which focuses largely on the ecological effects of human actions. Based on current evaluation practices within the Corps' and EPA's permit programs, it is shown that the commonly used screening approach to regulating wetlands uses is not compatible with the purposes of CIA, nor is the environmental impact statement (EIS) an appropriate vehicle for evaluating the variety of objectives and trade-offs needed as part of CIA. A heuristic model that incorporates the basic elements of CIA is developed, including the idea of trade-offs among social, economic, and environmental protection goals carried out within the context of environmental carrying capacity. 相似文献